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АСМ for students of Georgian Technical University

Strange number

Once afinancierponderedthe following question- is it possiblewithnegativetotalsfor each intervalof onemonthandthe same lengthof someof the reporting period, however, thesum totalof the sameperiodapositiveindicator.

Our task- to helphim in this.Required towrite a program thatfora given positiveinteger Ndeterminesthe total numberof numbers thathavethe aboveproperty for aperiodof lengthN.Iefor given Ntofind the numberofintegers nfor each of them, you cancreatea sequenceof length N,the sumof whose membersis positive,buteachsegment of lengthn inthe sum givesa negative number.

Input

The onlyline of input containsintegerN (1N2·1010).

Output

The output filea single number- the answerof the problem.

Time limit 1 second
Memory limit 64 MiB
Input example #1
2
Output example #1
0